Staff at human rights group Amnesty International have staged a fresh strike in a row over spending cuts and job losses.
Members of Unite manned a picket line outside the organisation's office in London after the union warned that plans to make £2.5 million worth of savings will lead to compulsory redundancies among the 200 employees.
Unite regional officer Alan Scott said: "While many appreciate cuts to staffing are inevitable, Amnesty management must stick to agreements they have signed and publicly stated they will honour in order to dispel the pervasive mistrust that has taken hold in the organisation.
"Dozens of staff face uncertainty about their immediate future. Many know that their posts will disappear before the end of 2012, but because management have torn up the redundancy policy, they have no idea of what will happen to them.
"Amnesty International cannot be an effective or credible human rights organisation if it does not respect the rights of its workers. The organisation's senior management must adhere to the same standards it demands of governments and corporations globally."
An Amnesty spokesman said: "We entirely respect the right of our staff to take strike action but regret that they feel the need to do so, particularly as the action is over how much money Amnesty International UK should contribute to increasing human rights work in the global South. That's something we cannot and wouldn't want to change.
"The highest decision-making body of the Amnesty movement, the International Council Meeting (ICM), made decisions on how much national sections like AIUK should contribute and how quickly this should rise, to increase Amnesty's work in the global South. The board of AIUK will abide by ICM decisions.
"Industrial action will not change this but we will remain in contact with union officials on this matter and on other substantive questions raised in the process of reducing costs at AIUK. We have been and will continue to work to keep redundancies to a minimum."
It was the third strike by Amnesty workers in recent weeks.